CN101573889A - Web/bulk transfer preallocation of upstream resources in a satellite communication system - Google Patents

Abstract

In a data over satellite system, preallocation of upstream channel resources is provided by a scheduler at the gateway satellite modem termination system (SMTS) in response from the user terminal, wherein the user terminal detects web browser and/or bulk transfers involving large amounts of data transfer from users via the upstream channel. A type length value (TLV) field is included with data packets transmitted to the gateway SMTS, at which excess transfer capability is allocated to the user terminal in anticipation of load requirements.

Description

The Web/ of upstream resource transmits preassignment in batch in the satellite communication system

The cross reference of related application

The application is hereby expressly incorporated by reference the full content of each following patent application:

With this PCT application PCT application the of " Improved Spot Beam Satellite GroundSystems " (temporarily with reference to the agent registration 017018-009510PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Multi-Service Provider SubscriberAuthentication " (temporarily with reference to agent registration 017018-007710PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Large Packet Concatenation In SatelliteCommunication System " (temporarily with reference to the agent registration 017018-008210PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Upfront Delayed Concatenation In SatelliteCommunication System " (temporarily with reference to the agent registration 017018-010510PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Map-Trigger Dump Of Packets In SatelliteCommunication System " (temporarily with reference to the agent registration 017018-010610PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Improved Spot Beam Satellite Systems " (temporarily with reference to the agent registration 017018-008010PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Downstream WaveformSub-Channelization For Satellite Communications " (temporarily with reference to the agent registration 026258-002400PC) by name of application on the same day _ _ _ _ number;

With this PCT application PCT application the of " Packet Reformatting For DownstreamLinks " (temporarily with reference to the agent registration 026258-002700PC) by name of application on the same day _ _ _ _ number;

With this PCT application on the same day application " Upstream Resource Allocation For SatelliteCommunications " (temporarily with reference to agent registration 026258-002800PC) by name the _ _ _ _ number PCT application;

No. the 60/828044th, the U.S. Provisional Patent Application of " Web/Bulk Transfer Preallocation ofUpstream Resources In A Satellite Communication System " (the agent registration 017018-010700US) by name of on October 3rd, 2006 application;

The U.S. that is called " Code Reuse Multiple Access For ASatellite Return Link " (agent registration 017018-001212US) in application on October 3rd, 2006 partly continues patent application No. 11/538431;

The U.S. that is called " Method For Congestion Management " (agent registration 017018-006110US) in application on October 3rd, 2006 partly continues patent application No. 11/538429.

Technical field

The present invention generally relates to radio communication, particularly satellite communication network.

Background technology

Along with the startup of the interspace Network of using the Ka band satellite, consumer's broadband satellite business is obtaining attraction in the North America.First generation satellite system although it is so can provide all told of a plurality of gigabits of every satellite per second (Gbps), but the design of such system has limited the consumer's that can suitably be served quantity inherently.In addition, the fact of striding a plurality of overlay areas dispersion capacity has further limited the bandwidth of each user (subscriber).

Although existing design has a plurality of capacity limit, for the still sustainable growth of demand of such broadband services.Several years in past have been seen the huge advance made in communication and the treatment technology.In conjunction with the system and the element design of selected innovation, this technology can be utilized to produce new wireless communication system and solve this demand.

The DAMA basis

DAMA user SM can operate and be used to send a request to DAMA scheduler or the SMTS that is positioned at gateway, asks enough upstream bandwidth to be sent in packet in its output queue.Ignore contention time-delay (contention delay) (that is, being used at the contention channel potentially conflicting but the contention time-delay that final success sends), the packet of arrival must wait for that shake hands the time interval (handshake interval) is up to having distributed bandwidth.Time interval of shaking hands is two-way time between terminal and the central controller (being SMTS in this case), is called as RTT.Terminal sends packet then, ignores transmitting time, and this packet will arrive central controller after half RTT.This processing means, does not include the contention time-delay, and all packets that arrive empty output queue will experience the time-delay of 1.5 * RTT.The time-delay of this 1.5 * RTT is the lower bound that can not reduce.

Move on to the formation head because the packet of arrival non-empty queue must be waited for up to them, so these packets will experience the total time-delay greater than 1.5 * RTT.Their time-delay is their stand-by period to add 1.5 * RTT.The DAMA scheduler attempts to minimize the stand-by period of the packet that arrives non-empty queue.

DOCSIS type DAMA (the Best Effort Demand Assigned Multiple Access that does one's best, BE-DAMA) and unique difference of pure DAMA be: can carry on the back for the request of bandwidth and carry (piggyback) on the back on the packet that sends, thereby unload some loads of contention channel and improve entire system capacity thus.This expression, the packet pulse that arrives docsis cable modem (CM) only has a contention time-delay for whole pulse.The request mechanism of this back carried is restricted to request the packet (packet that is being sent out takies the position 0 of output queue) of the position 1 that only is described in output queue.This means that first packet (P0) of pulse will have the time-delay of 1.5 * RTT, packet 1 will have the time-delay up to 2.5 * RTT, and packet 2 will have the time-delay up to 3.5 * RTT, or the like.

(Demand Assigned Multiple Access, DAMA) scheduler is useful for some load that are released in the channel that is subjected to contention in the demand assignment multiple access access.The purpose of DAMA scheduler in this example is, but reduce number in the upstream channel, that be assigned with the mini-slot (minislot) that is not used (promptly, improve dispatching efficiency), do not go up transfer performance and do not reduce the page download or the FTP that use this downstream channel.Final purpose is to provide more available upstream bandwidth so that each upstream is supported more users.According to the character of the burst transmissions of packet, the pulse of packet can only have a contention time-delay to whole pulse.Yet, since time that reaches of packet do not determine that so DAMA can produce the conflict of contention channel, produces invalid forthright that undesirable stand-by period and channel use thus.In order to raise the efficiency, what need is the mechanism that reduces the stand-by period.DAMA is in order to reach the potential instrument of this purpose in this mechanism.

Summary of the invention

According to the present invention, in the system of transmitting data via satellite (data over satellite system), by gateway satellite modem terminating systems (Satellite Modem Termination System, SMTS) scheduler of locating provides preassignment to the upstream channel resource in response to user terminal, and wherein user terminal detected by upstream channel comprising the Web browser that (involve) mass data transmits and/or transmit in batch from the user.Send in the packet of gateway SMTS and comprise that (typelength value, TLV) field are distributed superfluous transmission capacity at gateway SMTS place to the user terminal with loading demand to type lengths values.

To understand the present invention better by reference embodiment and accompanying drawing.

Description of drawings

Figure 1A and 1B are the block diagrams of satellite communication system;

Fig. 2 A and 2B are the maps of the geographical distribution of expression wave beam;

Fig. 3 is the block diagram of gateway system;

Fig. 4 is the block diagram of control system;

Fig. 5 is the communication of satellite relay and the block diagram of control assembly;

Fig. 6 A and 6B are the upstream transponder (upstream translator) of Fig. 5 and the block diagram of downstream translator (downstream translator);

Fig. 7 is the block diagram with user facility of user terminal;

Fig. 8 is the sequential chart of forward direction (forward) channel superframe;

Fig. 9 is the sequential chart of typical back channel superframe;

Figure 10 is the block diagram of gateway reflector;

Figure 11 is the block diagram of gateway receiver;

Figure 12 A and 12B are the charts of the Frequency Distribution of expression gateway;

Figure 13 is the block diagram of forward channel and back channel in repeater satellite;

Figure 14 is the chart according to state machine of the present invention;

Figure 15 is the chart that has the state machine of detailed description according to of the present invention;

Figure 16 A-C constitutes flow chart of the present invention from left to right together.

Embodiment

Various embodiment of the present invention comprises system, method, equipment and the software that is used for new broadband satellite network.Schematic embodiment only is provided in the embodiment, be not used in limit the scope of the invention, application or configuration.Opposite, the description subsequently of embodiment will provide the embodiment that can implement embodiments of the invention to those of ordinary skills.Can carry out various changes and without departing from the spirit and scope of the present invention to the function of assembly and layout.

Thus, different embodiment can omit, deduct or increase various processes or element rightly.For example, should be appreciated that in interchangeable embodiment, can be by coming manner of execution with described method different order, and can increase, omit or merge different step.And, also can be integrated among other different embodiment at the described feature of some embodiment.The different aspect and the assembly that can merge embodiment in a similar manner.In addition, before can embodiment below, need a plurality of steps afterwards or simultaneously.

Should also be appreciated that following system, method, equipment and software can be the elements of bigger system, wherein their application can preferentially be carried out or revise to other processes.

Figure 1A is the block diagram of the schematic satellite communication system 100 that disposes according to various embodiments of the present invention.This satellite communication system 100 comprises for example network 120 of internet, and network 120 is connected with gateway 115 interfaces, and gateway 115 is used for via satellite 105 and communicates by letter with one or more user terminals 130.Gateway 115 is called as hub or ground station sometimes.User terminal 130 is called as modulator-demodulator, satellite modem or user terminal sometimes.As mentioned above, though communication system 100 is illustrated as the communication system based on geostationary satellite 105, but should be noted that various embodiment described herein is not limited to use in the system based on geostationary satellite, for example some embodiment can be based on near-earth orbit (LowEarth Orbit, LEO) system of satellite.

In different embodiment, network 120 can be the network of any type, and can comprise for example internet, IP network, Intranet, wide area network (WAN), Local Area Network, Virtual Private Network, public switch telephone network (PSTN) and/or support the network of any other type of the data communication between the equipment described herein.Network 120 can comprise wired and wireless connections, comprises optical link.According to the disclosure, many for the person of ordinary skill of the art other examples are possible and tangible.As described in a plurality of embodiment, network can be by also being connected gateway 115 with other gateways (not shown) of satellite 105 communications.

Gateway 115 provides the interface between network 120 and the satellite 105.Gateway 115 can be used to receive data and the information of pointing to one or more user terminals 130, and these data and information can be formatd (format) 105 to be sent to each destination equipment via satellite.Similarly, gateway 115 can be used for from satellite 105 (for example, from the one or more user terminals) received signal of the destination of pointing to network 120, and the signal that receives can be formatd to transmit along network 120.

The equipment (not shown) that is connected to network 120 can be by gateway 115 and one or more user terminal communications.Can send data and information, for example IP datagram to gateway 115 from the equipment the network 120.Gateway 115 can format medium access control (MAC) frame so that be transferred to satellite 130 according to the physical layer definition.Some embodiment of the present invention can use various physical layer transmission modulation and coding techniques, comprises those technology of DVB-S2 and WiMAX standard definition.105 link 135 can be called as downstream uplink 135 hereinafter from gateway 115 to satellite.

Gateway 115 can use antenna 110 that signal is sent to satellite 105.In one embodiment, antenna 110 comprises paraboloidal reflector, and this parabola reflector has high directionality and has low directionality in other directions in satellite direction.Antenna 110 can comprise various interchangeable configurations and comprise the high efficiency of for example high isolation between the orthogonal polarization, operational frequency bands and operating characteristics such as low noise.

In one embodiment, geostationary satellite 105 is used for from the position of antenna 110 and frequency band and the particular polarization received signal that is sending.Such as, satellite 105 can use reflector antenna, lens antenna, array antenna, active antenna or other mechanism well known in the prior art to receive such signal.Satellite 105 can be handled the signal that receives from gateway 115, and will arrive one or more user terminals 130 from the signal forwarding that comprises mac frame of gateway 115.In one embodiment, satellite 105 sends a plurality of narrow beams that each points to the zones of different of the earth with the operation of multi-beam pattern, and tolerance frequency is reused.By such multi-beam satellite 105, can there be the unlike signal handover configurations of arbitrary number to satellite, allow between the difference wave beam, to switch from the signal of single gateway 115.In one embodiment, satellite 105 can be configured to " bend pipe (bent pipe) " satellite, wherein satellite carried out frequency translation with these signals resend their destination in the carrier signal that will receive before, and other processing are carried out or do not carried out to the content of signal hardly.Satellite 105 according to some embodiment of the present invention can use various physical layer transmission modulation and coding techniques, comprises those technology of DVB-S2 and WiMAX standard definition.For other embodiment, apparent for those of ordinary skills, a plurality of configurations are possible (for example, using LEO satellite or use to replace the mesh network (meshnetwork) of star network (star network)).

One or more user terminals 130 can receive the service signal that sends from satellite 105 by user antenna 125 separately.In one embodiment, antenna 125 and terminal 130 constitute very small aperture terminal together (Very Small Apeture Terminal, VSAT), antenna 125 are measured about 0.6 rice diameters and had about 2 watts of power.In other embodiments, can use the antenna 125 of various other types to come at user terminal 130 from satellite 105 received signals.130 link 150 can be called as downstream downlink 150 hereinafter from satellite 105 to user terminal.Each user terminal 130 can comprise the unique user terminal, perhaps comprises the hub or the router (not shown) that are connected to a plurality of user terminals alternatively.Each user terminal 130 can be connected to ustomer premises access equipment (Consumer Premises Equipment, CPE) 160, CPE 160 comprises for example computer, local area network (LAN), internet appliance, wireless network etc.

In one embodiment, multi-frequency time division multiple access (MF-TDMA) scheme is used for upstream link 140,145, allows effectively flowing of the traffic to keep the flexibility of partition capacity simultaneously between each user terminal 130.In this embodiment, can distribute a plurality of channels, these a plurality of channels be fix or distributed in more dynamic mode.Can also in each channel, use time division multiple access (TDMA) scheme.In this scheme, each channel can be divided into a plurality of time slots that can be assigned to connection (for example, user terminal 130).In other embodiments, can be with the one or more upstream links 140,145 of other arrangements, for example, mixing or other schemes of frequency division multiple access (FDMA), OFDM (OFDMA), code division multiple access (CDMA) or arbitrary number well known in the prior art.

User terminal, 130-a for example can be via satellite 105 be sent to network 120 destinations with data and information.User terminal 130 uses antenna 125-a by upstream up link 145-a signal to be sent to satellite 105.User terminal 130 can comprise the technology that defines in DVB-S2 and the WiMAX standard according to various physical layer transmission modulation and coding techniques, sends signal.In various embodiments, for each link 135,140,145,150, physical-layer techniques can be identical, perhaps can be different.115 link can be called as upstream downlink 140 hereinafter from satellite 105 to gateway.

Return Figure 1B, block diagram is used to represent the optional embodiment of satellite communication system 100.For example, this communication system 100 can comprise the system 100 of Figure 1A, but describes more in detail in this example.In this embodiment, gateway 115 comprises satellite modem terminating systems (Satellite ModemTermination System, SMTS), its at least in part based on wire cable data, services interface specification (Data-Over-Cable Service Interface Standard, DOCSIS).SMTS in this embodiment comprises a series of modulator and demodulator, is used for to user terminal 130 transmission signals with from user terminal 130 received signals.SMTS in the gateway 115 105 carries out the Real-Time Scheduling of signal communication amount via satellite, and the interface that is connected to network 120 is provided.

In the present embodiment, user terminal 135 also uses the modem circuit based on DOCSIS of part.Thus, SMTS can use resource management, agreement and scheduler based on DOCSIS to give information effectively.In different embodiment, can revise based on the element of DOCSIS and be used for wherein being suitable for.Thus, some embodiment can utilize some part of docsis specification, customizes other part simultaneously.

Though briefly described the satellite communication system 100 that can be used in different embodiments of the invention above, will describe the specific embodiment of such system 100 now.In this specific examples, to use the bandwidth of about 2 Gigahertzs (GHz), comprise the bandwidth of four 500 megahertzes (MHz) of adjacent spectra.The application of double-circle polarization causes comprising the usable frequency of the nonoverlapping bands of 8 500MHz with total available band 4GHz.This specific embodiment is used the multi-beam satellite 105 with gateway 115 and user's spot beam physical separation, and allows the frequency reuse at different links 135,140,145,150.Each service link spot beam on downstream downlink is used single travelling-wave tube amplifier (TWTA), and each TWTA operates to reach maximal efficiency in complete saturation condition.Single bandwidth carrier signal for example uses the whole of a 500MHz frequency band, fills the whole bandwidth of TWTA, allows the space hardware assembly of minimal amount thus.Spot beam size and TWTA power can be optimized to obtain the every square metre of every megahertz (dbW/m of flux peak density-118 dBw on the earth surface ²/ MHz).Thus, use approximate every hertz of 2 bits per second (bits/s/Hz), have the available bandwidth of about every spot beam 1Gbps.

Show the embodiment of forward link distribution system 1200 with reference to figure 12A.As shown in the figure, gateway 115 is connected to antenna 110, and this produces four downstream data flow signals.The single carrier wave that each use of four downstream uplink 135 is had the 500MHz frequency spectrum.In this embodiment, two frequencies and two polarization allow four independent downstream uplink 135 altogether, and only use the frequency spectrum of 1GHz.For example, link A 135-A can be the Freq 1U (27.5-28.0GHz) with left-handed polarization, link B135-B can be the Freq 1U (27.5-28.0GHz) with right-hand polarization, link C can be the Freq 2U (29.5-30GHz) with left-handed polarization, and link D can be the Freq 2U (29.5-30GHz) with left-handed polarization.

Four " bend pipe " that satellite 105 is described as between feeder link (feeder link) and the service link with being functionalized connects.105 " bend pipes " connect the direction that changes carrier signal and polarization via satellite.Satellite 105 is a downstream downlink signal 150 with each downstream uplink 135 conversion of signals.

Have four downstream downlink 150 in the present embodiment, each downstream downlink 150 provides service link for four spot beams 205.Downstream downlink 150 can change frequency in bend pipe as in the situation of present embodiment.For example, downstream uplink A 135-A 105 changes second frequency (that is Freq 1D) into from first frequency (that is Freq 1U) via satellite.Other embodiment also can change the up link of given downstream channel and the polarization between the down link.Some embodiment can use identical polarization and/or frequency with down link to the up link of given downstream channel.

Below with reference to Figure 12 B, show the embodiment of return link distribution system.This embodiment represents four upstream up links 145 from four groups of user terminals 125." bend pipe " satellite 105 adopts upstream up link 145, changes carrier frequency and/or polarization (not shown) alternatively, then they is directed to the spot beam that is used for gateway 115 again as upstream downlink 140.In this embodiment, carrier frequency changes between up link 145 and down link 140, and is identical but polarization keeps.Owing to be not in the overlay area of business beam to the feeder line spot beam of gateway 115, therefore can be to service link and feeder link the two to reuse identical frequency right.

Return Fig. 2 A and 2B, show the example of the multiple-beam system 200 of different embodiment according to the subject invention configuration.For example, this multiple-beam system 200 can be realized in the network 100 of Figure 1A and 1B description.There is shown the coverage of a plurality of feeder lines and professional spot beam zone 225,205.In this embodiment, satellite 215 comes reuse band by the certain zone that the directivity of antenna is isolated country (for example, the U.S., Canada or Brazil).Shown in Fig. 2 A, between feeder line and service point wave beam 205,225, there is geographical completely exclusiveness.But for Fig. 2 B is not such situation, has service point wave beam overlapping (for example 205-c, 205-d, 205-e) among Fig. 2 B in some example, and does not exist overlapping in other zones.Yet, by overlapping, have some interference problem, thereby may forbid the frequency reuse in the overlapping region.Four Color Pattern (Four Color Pattern) are even also provide the possibility that avoids interference under some overlapping situation of existence between the adjacent business beam 205./

In this embodiment, also show gateway terminal 210 and feeder beam 225 thereof.Shown in Fig. 2 B, gateway terminal 210 can be positioned at the zone (for example, first, second and the 4th gateway 210-1,210-2,210-4) that is covered by the service point wave beam.Yet gateway also can be positioned at outside the zone that the service point wave beam covers (for example the 3rd gateway 210-3).By outside the zone that gateway terminal 210 is arranged at service point wave beam covering (for example the 3rd gateway 210-3), realize that geographical separation is to allow to reuse the frequency of distribution.

In given feeder line spot beam 225, there is standby gateway terminal 210 usually.If primary gateway terminal 210-4 work is undesired, this standby gateway terminal 210-5 can substitute primary gateway terminal 210-4.In addition, can when damaging because of weather, the primary gateway terminal use this standby gateway terminal.

Below with reference to Fig. 8, show the embodiment of downstream channel 800.Downstream channel 800 comprises a series of continuous superframes 804, and each superframe 804 can have identical size or vary in size.This embodiment is divided into a plurality of pseudo channels 808 (1-n) with superframe 804.Pseudo channel 808 (1-n) in each superframe 804 can be identical size or vary in size.Can between different superframes 804, change the size of pseudo channel 808 (1-n).Can use different coding alternatively to different pseudo channel 808 (1-n).In certain embodiments, pseudo channel is the same short with a symbol (symbol) on the duration.

With reference to figure 9, show the embodiment of upstream channel 900.Present embodiment uses MF-TDMA, but other embodiment can use CDMA, OFDM or other access schemes.In one embodiment, upstream channel 900 has the whole bandwidth of 500MHz.Whole bandwidth is divided into m frequency subchannels, and each frequency subchannels can be different on bandwidth, modulation, coding etc., and also can be different on the time that needs based on system.

In the present embodiment, provide two dimension (2D) map (two-dimetional (2D) map) to each user terminal 130 and be used for its Upstream Traffic.This 2D map has a plurality of clauses and subclauses, each clauses and subclauses indication frequency subchannels 912 and time period 908 (1-5).For example, a user terminal 130 has been assigned with subchannel m 912-m, time period one 908-1; Subchannel two 912-2, time periods two 908-2; Subchannel two 912-2, time periods three 908-3 etc.Needs in advance according to scheduler among the SMTS come each user terminal 130 is dynamically adjusted the 2D map.

With reference to Figure 13, show the embodiment of channel mapping.Only show the channel of single feeder line spot beam 225 and single service point wave beam 205, but embodiment can comprise many spot beams 225,205 (for example, different embodiment can have for example 60,80,100,120 every type spot beam 225,205).Forward channel 800 comprises n the pseudo channel 808 that advances to service point wave beam 205 from gateway antennas 110.Each user terminal 130 can be assigned with one or more pseudo channels 808.M the back channel 900 that MF-TDMA channel 912 is formed between user terminal (ST) antenna 125 and the feeder line spot beam 225.

Below with reference to Fig. 3, show the embodiment of the ground system 300 of gateway 115 with the block diagram form.For example, an embodiment can have 15 has source gateway 115 (with possible standby gateway) to generate 60 service point wave beams.Ground system 300 comprises a plurality of gateways 115 that are connected to antenna 110 respectively.All gateways 115 are connected to for example network 120 of internet.Network is used to collect the information of user terminal.In addition, each SMTS uses network 120 or other not shown means to come and other SMTS and Internet traffic.

Each gateway 115 comprises transceiver 305, SMTS 310 and router three 25.Transceiver 305 comprise reflector and receiver the two.In this embodiment, reflector obtains baseband signal, and this baseband signal is carried out up-conversion and amplification, is used for the transmission by the downstream uplink 135 of antenna 110.Receiver carries out down-conversion and tuning with other processing as described below to this upstream downlink 140.SMTS 310 processing signals are with permission user terminal requests and reception information, and SMTS 310 is forward direction and back channel 800,900 scheduling bandwidths.In addition, SMTS 310 provides configuration information and receives the state of user terminal 130.Information any request or back is all passed through router three 25 and is transmitted.

With reference to Figure 11, show the embodiment of gateway receiver 1100.The embodiment of this receiver 1100 handles four back channels 900 of four different business spot beams 205.Can use antenna polarization and/or filtering 1104 in four paths, to divide back channel 900.Each back channel is connected to low noise amplifier (LNA) 1108.Down-conversion 1112 drops to signal mixing its intermediate frequency.A plurality of tuners 1116 separate each upstream subchannel 912 from signal.In SMTS 310, carry out further and handle.

Below with reference to Figure 10, show the embodiment of gateway reflector 1000.Receive the downstream channel 800 of intermediate frequency from SMTS 310.By the path of separating, use two different carrier frequencies to come each downstream channel 800 is carried out up-conversion 1004.Power amplifier 1008 increased the amplitude of forward channel 900 before being connected to antenna 110.The signal of 110 pairs of separation of antenna polarizes and keeps four forward channels 800 inequality when they are passed to satellite 105.

With reference to figure 4, show the embodiment of SMTS 310 with the block diagram form.The gateway that separates on a plurality of geography 115 pairs inbound (inbound) and (outbound) link 135,140 that sets off are finished Base-Band Processing.Each SMTS 310 is divided into two parts usually, is specially, and sends information to the downstream data flow part 305 of satellite 105 and receives the upstream part 315 of information from satellite 105.

(Downstream, DS) blade (blade) 412 obtains information from construction of switch (Switch Fabric) 416 to downstream data flow part 305 by a plurality of downstream data flows.In a plurality of downlink data flow-generators 408, divide DS blade 412.This embodiment comprises four downlink data flow-generators 408, each downstream channel 800 corresponding downlink data flow-generator 408.For example, this embodiment uses the 500MHz spectral range of four separation with different frequency and/or polarization.Four dispersive modulators (Four ColorModulator) 436 have respectively the modulator for each DS generator 408.The modulated signal of intermediate frequency is coupled to the transmitter portion 1000 of transceiver 305.In four downlink data flow-generators 408 of this embodiment each has J virtual DS blade 412.

The upstream part 315 of SMTS 310 receives and process information from satellite 105 with the base band intermediate frequency.After the base band upstream signal of 1100 pairs of four separation of receiver portion of transceiver 305 produced all subchannels 912, each subchannel 912 was coupled to different demodulator 428.Some embodiment can comprise switch before demodulator 428, thereby allowed to forward arbitrary return link subchannel 912 to arbitrary demodulator 428 to allow dynamically assigning again between four back channels 908.A plurality of demodulators are specifically designed to upstream, and (Upstream, US) blade 424.

US blade 424 is used for recovering this information before the information that will receive from satellite 105 is being provided to construction of switch 416.US scheduler 430 on each US blade 424 is used for the use to each user terminal 130 scheduling back channels 900.Can assess the further needs of the user terminal 130 of specific back channel 900, and cooperate with explorer and load equalizer (RM/LB) piece 420 and correspondingly to adjust bandwidth/stand-by period as required.

RM/LB piece 420 distributes the traffic among US and the DS blade.By communicating by letter with other RM/LB pieces 420 among other SMTS 310, each RM/LB piece 420 can be assigned to other gateways 115 again with user terminal 130 and channel 800,900.Can for example, be deficient in resources and/or the load consideration owing to the such appointment again of reason generation arbitrarily.In this embodiment, in a plurality of RM/LB pieces 420, make this decision with distributed way, but other embodiment can by a main MR/LB piece or at certain other center determination means make this decision.For example, assigning again of user terminal 130 can be used overlapping service point wave beam 205.

Below with reference to Fig. 5, show the embodiment of satellite 105 with the block diagram form.Satellite 105 among this embodiment uses 60 feeder lines to communicate by letter with whole ST 130 with 15 gateways 115 with service point wave beam 225,205.Other embodiment can use or more or less gateway/spot beam.For example using, the energy of chemical fuel, nuclear fuel and/or sonar energy provides Pasteur (buss) energy 512.Satellite controller 516 is used to keep attitude (attitude) and controls satellite 105 from other aspects.Can upload the software upgrading of satellite 105 from gateway 115, and carry out this software upgrading by satellite controller 516.

Information 105 is transmitted on both direction via satellite.Downstream translator 508 uses 60 service point wave beams 205 to relay information to user terminal 130 from 15 gateways, 115 reception information.The user terminal 130 reception information of upstream transponder 504 from taking these 60 spot beam zones, and with this information relay to these 15 gateways 115.The satellite of present embodiment can switch carrier frequency in downstream data flow or the upstream data stream handle 508,504 in the mode of " bend pipe " configuration, but other embodiment can carry out baseband switching between different forward directions and back channel 800,900.The frequency of each spot beam 225,205 and polarization can be programmable or pre-configured.

With reference to figure 6A, show the embodiment of upstream transponder 504 with the block diagram form.All return link information conducts that receiver and low-converter (Rx/DC) piece 616 receives for the zone that is defined by spot beam 205 transform to intermediate frequency (IF) analog signal before.All there is Rx/DC piece 616 in each professional spot beam zone 205.IF switch 612 is routed to specified upstream data flow downlink channel with particular baseband signal from Rx/DC piece 616.Use upconverter and travelling-wave tube amplifier (UC/TWTA) piece 620 to fill the upstream downlink channel.Can change frequency and/or polarity by this processing, make that each upstream channel can be by the satellite 105 of bend pipe form.

Each gateway 115 has four special-purpose UC/TWTA pieces 620 in upstream transponder 504.In the present embodiment, two of four special-purpose UC/TWTA pieces 620 in the first frequency range operation, and two in the second frequency range operation.In addition, two are used right-hand polarization, and two are used left-handed polarization.Between two polarization and two frequencies, satellite 105 can be communicated by letter with each gateway 115 by the upstream downlink channel of four separation (separate).

Below with reference to Fig. 6 B, show the embodiment of downstream translator 508 with the block diagram form.Each gateway 115 has four downstream uplink channels to satellite 105 by using two frequency ranges and two kinds polarization.Rx/DC piece 636 obtains analog signal and is intermediate frequency with this signal transformation.All there is Rx/DC piece 636 in whole 60 downstream uplink channels from 15 gateways 115.The particular channel 800 that IF switch 612 connects from gateway 115 to specific transactions spot beam 205.Each IF signal from switch 628 is modulated and amplification by UC/TWTA piece 632.Antenna use spot beam with signal broadcasting to the user terminal 130 that takies spot beam zone.Identical with upstream transponder 504, downstream translator 508 can change the carrier frequency and the polarization of specific downstream channel with the bend pipe form.

Fig. 7 comprises the block diagram of representing one group of subscriber equipment 700, and subscriber equipment 700 can be positioned at customer location to receive and to send signal of communication.For example, the element of this group subscriber equipment 700 comprises antenna 125, the user terminal 130 and the Any user end equipment (CPE) 160 of being correlated with, and ustomer premises access equipment 160 can be computer, network etc.

Antenna 125 can be from satellite 105 received signals.Antenna 125 can comprise VSAT antenna or arbitrarily different other antenna types (for example, other parabolic antennas, microstrip antenna or helical antenna).In certain embodiments, antenna 125 can be configured to dynamically revise its configuration come certain frequency range or from certain position received signal better.Signal (may after the processing of certain form) is forwarded to user terminal 130 from antenna 125.User terminal 130 can comprise radio frequency (RF) front end 705, controller 715, pseudo channel filter 702, modulator 725, demodulator 710, filter 706, downstream data flow protocol conversion device 718, upstream protocol conversion device 722, receive (Rx) buffer memory 712 and send (Tx) buffer memory 716.

In the present embodiment, RF front end 705 has transmission and receiving function.Receiving function comprises the amplification (for example, by low noise amplifier (LNA)) to the signal that receives.This amplifying signal of down-conversion (for example, using frequency mixer to merge) then with amplifying signal with from the signal of local oscillator (LO).This down signals can be exaggerated by RF front end 705 before the processing of carrying out superframe 804 by pseudo channel filter 702 once more.Select the subclass of each superframe 804 by pseudo channel filter 702 from downstream channel 800, for example, one or more pseudo channels 808 are used for further processing by filtering.

Can use various modulation and coding techniques at user terminal 130, be used for from satellite signal that receives and the signal that is sent to satellite.In the present embodiment, modulation technique comprises BPSK, QPSK, 8PSK, 16APSK, 32PSK.In other embodiments, extra modulation technique can comprise ASK, FSK, MFSK and QAM, and various analogue technique.Demodulator 710 can the demodulation down signals, and the pseudo channel after the demodulation 808 is forwarded to filter 706 to give the data of specific user terminal 130 with planning and other information of pseudo channel 808 are peeled off.

Isolate the agreement that the protocol conversion that downstream data flow protocol conversion device 718 will be used for satellite link becomes DOCSIS MAC piece 726 to use in case will go to the information of specific user terminal 130.Optional embodiment can be used WiMAX MAC piece or combination DOCSIS/WiMAC piece.The pulses switch that Rx buffer memory 712 is used for receiving at a high speed is DOCSIS MAC piece 726 manageable low rate data streams.DOCSISMAC piece 726 is to receive the DOCSIS data flow and manage the circuit that this data flow is used for CPE 160.The task that DOCSIS MAC piece 726 is managed for example supply, Bandwidth Management, access control, quality of service etc.CPE can use Ethernet, WiFi, USB and/or other standard interfaces to be connected with DOCSIS MAC piece 726 usually.In certain embodiments, can use WiMAX piece 726 to replace DOCSIS MAC piece 726 to allow to use the WiMAX agreement.

It should be noted that equally, though the packet that downstream data flow protocol conversion device 718 and upstream protocol conversion device 722 can be used for receiving is transformed into DOCSIS or the compatible frame of WiMAX to be handled by MAC piece 726, these converters in many examples not necessarily.For example, in the embodiment that does not use based on the element of DOCSIS or WiMAX, the agreement that is used for satellite link also can be compatible and do not carry out such conversion with MAC piece 726, and can get rid of converter 718,722 thus.

The various functions of controller 715 managing user terminals 130.Controller 715 can monitor various decoding of the prior art, interweaves, decoding and descrambling technology.Controller can also be managed the function that can be applicable to data signal and that handle with one or more CPE 160 exchanges.CPE 160 can comprise one or more user terminals, for example personal computer, kneetop computer or other calculation elements arbitrarily of the prior art.

Controller 715 realizes in one or more application-specific ICs (ASIC) with other elements of user terminal 130, but perhaps realizes at the general purpose processor that is used for carrying out application function.Alternatively, can in one or more integrated circuits, carry out the function of user terminal 130 by one or more other processing units (or nuclear).In other embodiments, can use the integrated circuit (for example, structure/platform ASIC, field programmable gate array (FPGA) and other semi-custom IC) of other types, it can be by any-mode programming well known in the prior art.Can be to controller programming with accessing memory cells (not shown).Controller can be from memory cell instruction fetch and other data, perhaps with the writing data into memory unit.

As mentioned above, can be in various signals of communication with data from CPE 160 by the user terminal 130 up satellites 105 that are sent to.Thus, CPE 160 can be sent to data DOCSIS MAC piece 726, to be converted to the DOCSIS agreement before upstream protocol converter 722 translation protocol.Low speed data is waited in Tx buffer memory 716 up to its link pulse transmission via satellite.

The data of Chu Liing send to modulator 725 from Tx buffer memory 716 then, use a kind of technology in the aforesaid technology to come the data of modulation treatment here.In certain embodiments, can in these transmission, use self adaptation or variable coding and modulation technique.Particularly, according to 105 signal quality specification, combination or " mould sign indicating number (modcode) " of different modulating and coding can be used for the different pieces of information bag from antenna 125 to satellite.For example block up other factors of problem of network and satellite also can be to determine factor.Can be from satellite or other source received signal quality information, and can make in controller this locality or the long-range various decisions of making about mould sign indicating number application.RF front end 705 can amplify signal with up-conversion modulation to transfer to satellite by antenna 125 then.

Be the description of peculiar aspect of the present invention below.

WEB/BULK transmits preassignment

The preassignment that web triggers and in batch transmission (bulk transfer) all be considered to " preassignment ".Under the situation that web triggers, the SMTS scheduler is authorized in the mode of prediction (speculative) based on the arrival of true request.Under situation about transmitting in batch, the mode preassignment of scheduler to measure is sought upstream mandate speed and the upstream request of transmitting in batch are complementary.

The preassignment general view that web triggers

When the load of upstream is light, excess bandwidth predictably can be pre-assigned to active user.This has used otherwise may become the bandwidth that is not used, and this will speed up user's web and browses response.Along with the increase of load, SMTS will forbid the preassignment that web triggers.This is described as " according to the web preassignment of load " in the back.

The preassignment that web triggers is used web to sign and is discerned http session and carry out preassignment subsequently.Always authorize (obey and authorize the mini-slot restriction) in couples.First authorizes based on true request, and second authorizes the prediction mandate that is based on paQuanta.

Ideally, in the MTD system, two (serial connection) frames are arranged at SM.A frame is in HWQ, and another is in SWQ.When authorizing arrival (true mandate back is and then predicted and authorized) for two, if second mandate is guessed that correctly output queue will emptying.When this thing happens, the frame of the next HWQ of arrival will generate request at accidental channel.In order to reduce the use of this accidental channel, the tight back that mirage packet (describing among the 3.4.5.4.2) is inserted in the S-HoQ frame is carried request on the back to form the back of the body.

Transmit general view in batch

The feature of any MAC agreement based on DAMA is each two-way time (round-trip-time, RTT) frame of exchange.This with the upstream rate limit is:

Equation 1

In particular design, upstream PHY configuration is restricted to maximal uplink flow transmission size about the 4K byte.Transmit if the user is carrying out the FTP of 1500 byte data bag sizes in the upstream, this can make XTP send a serial connection frame (4.5 kilobytes will surpass the serial connection threshold value) of 3000 byte-sized in each two-way time.We are used for the two-way time of MTD-DAMA usually between 600 to 650 milliseconds.This result who brings is the throughput of about 38Kb/s.

Use the Surfbeam of DAMA need be for transmitting the upstream throughput that can reach 512Kb/s in batch, and therefore need make amendment to allow this throughput DAMA.

(Bulk Transfer over DAMA BToDAMA) has regulated the idea of having implemented among the Doc in transmission in batch on the DAMA.These ideas are the preassignment that drives of client, use agreement identification and mirage packet (Phanton Packet, the P of signature ²) insert.BToDAMA has also introduced increases the greedy algorithm of upstream data flow rate with visible minimum speed limit among coupling CoS speed or the WAN.

The BToDAMA hypothesis is used basic DAMA mechanism, i.e. the back of the body request of carrying on the back and each RTT authorize a bandwidth.BToDAMA uses unified privately owned TLV (pTLV), and pTLV seeks the transmission of just having discerned in batch (BT) and expects which additionally authorizes scheduler and communicates by letter.As in the preassignment version 2, pTLV does not replace the back of the body of hardware generation and carries request on the back, and the back of the body that pTLV and hardware generate is carried on the back does not have time relationship closely yet between the request.

Behind identification BT,, the upstream data flow rate can realize terminal CoS speed and minimized bandwidth waste simultaneously thereby need being set.This relates in mode greediness, that speculate increases the upstream data flow rate up to reaching CoS speed, or scheduler can be used in appointment without any more bandwidth, perhaps up to since the path more the bottleneck of below cause any extra upstream bandwidth to be wasted.

Web and batched communication (Simultaneous Web and Bulk Traffic) synchronously

When the CPE of single SM back (or CPE network) was carrying out BT and uploads with page download, we need ask maximum (CoS) speed.For this reason, we have and have precedence over the web perception algorithm and allow modulator-demodulator to enter into the mechanism of batch mode.This mechanism is calculated the number of the packet that surpasses 1000 bytes (with after MAC the affix and before serial connection) in the sliding window (current is 10) that with the second is unit.If more than threshold value (current is 10), SM can force and oneself jump out the WEB pattern and transfer BULK to during this period.When packet was less than threshold value, SM as above operated.

Privately owned TLV

Ideational form below privately owned TLV (pTLV) will adopt.

struct UnifiedpTLV{

type

length

application

paQuanta

paMultiplier

}

Application field identification application state.This field adopted value NULL, WEB and BULK.This field should be that dibit is long.If if forbid application-specific or use being identified, the application field is set to NULL.The identification of paQuanta field is the preassignment mandate size of unit with the minimum authorization size (i.e. 138 bytes) with byte representation.This field should be 6 bit lengths.(perhaps using unsettled mandate preferably can finish) that paMultiplier indication SMTS scheduler must be assigned continuously a certain size number (the number of individual grants ofsize paQuanta mini-slots) of each mandate of mini-slot of paQuanta.This field should be 8 bit lengths.

The function of SMTS

When receiving request by the request channel or by the request that the back of the body is carried on the back, the SMTS scheduler should be cashed this request (standard DAMA behavior) and if can provide another mandate or other mandates then in identical MAP.Use for arbitrary preassignment, the action of SMTS scheduler is identical.The SMTS scheduler must distribute the paMulitipler of the mini-slot (size paQuantamini-slots) of a certain size paQuanta to authorize.If scheduler can not distribute whole authorization numbers, must emphasize " authorizing unsettled " and in next MAP interval, assign remainder.

SMTS need keep state for the SM of each registration.The state that need keep is comprised among the pTLV just, i.e. Shi Bie application (NULL, BULK or WEB), current preallocation amount (with the paQuanta of mini-slot metering), and paMultiplier.

Each when receiving pTLV, the update mode table.Termination (expiry) value also should be arranged.Each when receiving pTLV, the update mode table also also upgrades stop value.If do not receive pTLV in a period of time, should remove the state table of this SM.This helps garbage reclamation.Termination should be approximately half a minute.

The update mode table separates with generation preassignment mandate.Not free relation between the two.Receive whenever pTLV, all the update mode table.Each providing when true request arrives predicts that mandate and state table show that SM is asking preassignment.Therefore, scheduler use＜paQuanta, paMultiplier〉very little hysteresis is arranged between value and this value value (i.e. the value of Geng Xining) that will change over.Therefore, for example, arrive, then very may at first consider this request, and make the preassignment mandate based on the value in the state table of not this up-to-date pTLV renewal if having the serial connection packet of the pTLV of back of the body request of carrying on the back and renewal.When frame (this very may after handling the request that the back of the body carries on the back) when upstream preprocessor piece occurs, will use pTLV to come the update mode table.Trial make request and pTLV have between upgrading tight time relationship be bother very much and may be infeasible.

The character loan of Web (credit-borrowing) only

Standard among the SMTS type algorithm of doing one's best has " character loan " feature and subsidizes the deficit round robin of oneself (it is that this Business Stream is used that Deficit Round-Robin, DRR) algorithm, DRR algorithm allow Business Stream to keep the front to authorize remaining credit.This helps grant authorization so that obtain business quickly and avoided circulation unnecessary in the DRR algorithm.This feature only is applied to carry the mandate of asking on the back by the back of the body, thereby expression SM has deposit (backlog).Accidental channel request mandate is zero from credit value.

In DAMA implements, thereby this algorithm this character loan feature of making amendment only is applied to be identified as the stream of Web.All other requests are zero from credit value all.This can help to carry out the back of the body and carry the web stream of request on the back and web stream is given than (back of the body is carried on the back or other) or accidental channel in batch (suppose be non-deposit) the slightly high service priority of request.

Web preassignment based on load

Because superfluous available channel bandwidth is used in design web preassignment, expectation need be forbidden web preassignment when channel becomes congested.This requires reliable congested index (metric).Such index is to measure as the percentage of the MAP mini-slot of congested time slot.Undertaken by definition time window (providing), accumulation spreads all over the whole M AP mini-slot and the whole congested time slot that spreads all over window of window on this time window.Also provide threshold value, expression is to the percentage of the congested contention of the formation of channel.When each window stops, calculate contention space percentage and memory contention space percentage divided by total MAP mini-slot for window by contention slots with accumulation.Empty accumulator for next window then.When bandwidth on demand (perhaps the accidental channel or the back of the body are carried on the back), be lower than threshold value if check above percentage and this percentage, forbid preassignment in the time of request.If be higher than threshold value, allow web preassignment.This algorithm is not suitable for and transmits preassignment in batch.

The application state machine

With reference to Figure 14, (Application State Machine ASM) provides and has known about helping the means of preallocated modem state the application state machine.When detecting when transmitting in batch, no matter current state how, ASM is transformed into the BULK state.When at the NULL state, if detect movable or one of the transmission in batch of web, then ASM is transformed into appropriate state.SM always is to use ASM signal (signal).Under the situation of channel congestion, SMTS will ignore WEB preassignment.SMTS always authorizes the BULK pre-allocation request, up to manually being forbidden.

Whenever modulator-demodulator detects new page download session, and ASM is transformed into the WEB state and uses web quanta to upgrade pTLV paQuanta (the paMultiplier field will be set to 1).If there was not new trigger event to take place in several seconds, then ASM withdraws from the WEB state and moves to BULK or NULL according to the state of BULK index.

The traffic that satellite modem detects visit and web inquires about the port (for example port 80) that is associated whenever begins 5 seconds timers (if or moved then restart).Stop (promptly the web inquiry had had 5 seconds from last time) up to this timer, no matter index how in batch, SM can ask web preassignment.When the timer termination, SM can move to any state (BULK or NULL) of the current indication of index in batch.

Transmit in batch and detect

Using three indexs to detect in batch transmits.Announce to transmit in batch when satisfying specific criteria when any two in this index, ASM is transformed into the BULK state, constitutes pTLV according to the regulation that transmits in batch then.

Transfer rate index-index 1 in batch

By measuring the arrival rate that the arrival rate that arrives SWQ generates windowization.This speed should be measured with bps (b/s), averages on configurable window.

If window speed index M ₁Surpass 30Kb/s, with designator I ₁Be set to TRUE.

Because the fluctuation of the arrival rate that the end-to-end current control of PEP causes, this speed index may not be good designator after transmission is in stable state in batch, but almost can trigger immediately after entering in batch.

Transmit reservation index-index 2 in batch

By being recorded in (serial connection) frame byte deposit the HWQ when SWQ is dumped to HWQ is generated average byte deposit among the HWQ.Must before dump, measure the byte deposit.This index must be a sliding window, and the deposit of therefore measuring must stored in the buffer memory (ring buffer) by turns.Must accumulating by turns, buffer memory removes this accumulation then to obtain mean value.For this reason, the suggestion by turns size of buffer memory is 2 power, thereby division is simply to move to right.Rotate buffer memory S _RB-2Size be experiment parameter, yet initial value should be 8.This average byte deposit forms M ₂Work as M ₂Surpass threshold value 2 (T ₂) time, with the designator I of index 2 ₂Be set to TRUE.

${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="A20078004010200451.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=(\underset{i}{\mathrm{\&Sigma;}}\mathrm{ring}\_\mathrm{buffer}\left(i\right))>>{\log }_2{S}_{\mathrm{RB}-2}$ Equation 2

M ₂Be the good index when transmitting beginning in batch, yet when reaching stable state, deposit will diminish, so this index will become FALSE.

The T that is used for initially integrated (integration) and test ₂Value is 1500 bytes.

Transmit reason index-index 3 in batch

At every turn will (serial connection) frame when SWQ is dumped to the HWQ, the reason of dump is converted to integer value and is stored in rotate in the buffer memory.During when accumulation with divided by buffer memory by turns big or small, buffer memory forms sliding window average by turns.Use by turns buffer memory to generate and New Set 3 more M constantly in each dump then ₃Import this value of rotating buffer memory and follow the dump reason that provides in the table 1.

Table 1

The dump reason	Input value
		Authorize and arrive	0
The UDC timer stops	0
		The mirage packet is by dump	128
Reach the serial connection threshold value	255

Once more suggestion by turns the size of buffer memory be 2 power, thereby division is simply to move to right.Equation 3 provides index M ₃

$M3=(\underset{i}{\mathrm{\&Sigma;}}\mathrm{ring}\_\mathrm{buffer}\left(i\right))>>{\log }_2{S}_{\mathrm{RB}-3}$ Equation 3

Work as M ₃Surpass T ₃The time, be used for the designator I of index 3 ₃Be set to TRUE.For initially integrated (integration), S _RB-2Should be set to 8, T ₃Should be set to 80.

The good designator that index 3 transmits in the time of should being when beginning and stable state in batch, and therefore can be as from beginning the anchor point that identification transmits in batch to the processing of stable state.

Event driven state machine

With reference to Figure 15, event driven state machine (Event Driven State Machine, the instruction that how SM will move when ESM) providing hypothesis that incident has taken place.There are four kinds of different incidents.

1.UDC timer stops

2.PDU arrive SWQ

3. frame data bag descriptor is recovered

4. the MAP that has mandate arrives

ESM has been shown among Figure 15.This state machine is supported preassignment (PAv2) and the BToDAMA that Web triggers, and other function.

(serial connection) frame that is in the SWQ head is called as " cp2 ".

Can be directly and action when being clear that the UDC timer stops from Figure 15.

When PDU arrived, it both be not concatenated into existing frame, did not become first packet of new serial connection group yet.

When data collection bag descriptor, SM will move A to C.When carrying out function R eclaimTxFrames (), the frame that this representative sends or the end of frame fragment.When carrying out ReclaimTxFrames (),, known (serial connection) frame just upgrades VQ if having finished transmission.This design need not be supposed the character of ReclaimTxFrames ().If called ReclaimTxFrames () when each transmission fragment rather than whole (serial connection) frame, then the state machine of Figure 15 will normally move.

When the MAP with mandate arrived, this action was more complicated and will be described below.

The virtual queue that is used for computed in software

Introducing the notion of virtual queue (VQ) comes with the storage vault that acts on calculating.When (serial connection) frame by when SWQ is dumped to HWQ, its byte-sized is recorded among the VQ as clauses and subclauses.

The VQ clauses and subclauses will adopt abstract form:＜Frame Id 〉,＜Bytes Remaining 〉,＜FragmentedFlag 〉,＜Done Flag 〉,＜HWQ Empty Upon Dump Flag 〉,＜Phantom Packet Flag〉and＜Final Frame Flag 〉.For purpose of description, the structure below clauses and subclauses adopt.

struct VQEntry{

list_of_frameIds

bytesRemaining

fragmentedFlag

doneFlag

heudFlag

p2Flag

finalFrameFlag

}

When (serial connection) frame from SWQ during to the HWQ dump, if frame is the frame of non-serial connection, then the VQEntry.bytesRemaining value is the total length (total_len) of frame, if perhaps frame is the frame of serial connection, then the VQEntry.bytesRemaining value is the serial connection length (concat_len) of frame.

Field VQEntry.list_of_frameIds must be selected to represent entire frame.When carrying out function R eclaimTxFrames (), packet descriptor and buffer descriptor are recovered and are used for the SW use.When (serial connection) frame is fully sent (that is, not having rest segment in HWQ), then removing is in the clauses and subclauses of VQ head.When having reclaimed the entire packet among the list_of_frameIds, can remove these clauses and subclauses.

If through segmentation, then segmentation markers is set to TRUE to (serial connection) frame in its whole transmission course.

Finish mark and represent that the SW of the progress in the hardware queue understands.

If (serial connection) frame of being represented by these VQ clauses and subclauses is placed in the empty hardware queue (heud=Hardware queue Empty Upon Dump), then the heudFlag field is set to TRUE.This field is represented not only should can send a request to accidental channel by (serial connection) frame, and in this (serial connection) frame back mirage packet (phantom Packet) should be set in HWQ.

Be actually mirage packet (Phantom Packet, P if just be dumped to the frame of SWQ ²), then the p2Flag field is set to TRUE in the VQ clauses and subclauses.For every other frame, this is set to FALSE.

If by the frame of dump be since a series of mandates in last mandate and just by dump, then the finalFrameFlag field is set to TRUE in the VQ clauses and subclauses.Usually only the mirage packet is provided with this mark.This will be described in greater detail below.

Drive the degree of depth of VQ by the needs that transmit in batch.The serial connection restriction of supposing us is～4000 bytes and upstream data flow rate are 512Kb/s.This XTP send window (650 milliseconds * 512Kb/s * 1.5/8) corresponding to 62400 bytes.If we adopt this value and with this value divided by 4000, then will cause the frame of 16 serial connections; VQ must have 16-20 clauses and subclauses at least thus.

The authorisation process flow process

When MAP arrived SM, hardware and software was analyzed by MAP.When MAP arrived, software must be carried out preliminary treatment and produce tuple (tuple)＜grantSizeInBytes, lastGrantFlag 〉.The tuple that is authorized to makes lastGrantFlag be set to TRUE, if this is to distribute to last mandate of particular terminal and do not have " authorizing unsettled " for this terminal in MAP.Otherwise lastGrantFlag is set to FALSE.

Be arranged to first group pattern in case in MAP, be assigned to whole mandates of specific SM, can authorize the flow chart of tuple execution graph 16A-C so each.

This flow chart is supported MTD, PAv2 and BToDAMA.

When authorizing arrival, monitor that this mandate is to determine whether and the S-HoQ frame will be dumped to HWQ from SWQ.This is the MTD behavior of standard.Preassignment (Web trigger and in batch the two) has added extra requirement in use to limit accidental channel.This extra requirement is " a mirage packet ".When the series mandate that arrives not only emptied HWQ but also empties SWQ, the mirage packet was dumped to HWQ from SWQ.Mirage packet (P ²) be to be abandoned and will be fit to the frame of single turbo code word (33-35 byte) by SMTS.To insert the mirage packet to other disabled mandates.The mirage packet will be used to PAv2 and BToDAMA to keep the DAMA channel effectively and be in outside the accidental channel.If source (source) becomes inactive (go silent), then will no longer insert the mirage packet.The mirage packet is that to have ID be 252 upstream MAC administrative messag.

All mirage packets must carry pTLV.At dump incident (the dump incident or the P of the frame of serial ²The dump incident) should finish update all before to pTLV.

Requirement in the dump incident

Because the UDC timer has stopped, reached the mandate of serial connection threshold value or triggering dump and arrived, therefore (serial) frame can be dumped to HWQ from SWQ.

For all these situations,, must monitor that then the buffer memory of HWQ takies if (ASM's) appState is set to BULK.If HWQ is empty, increase progressively counter so as SID specific (that is, all frames for SID inside are overall) title HWQEmptyCounter.If HWQ is a non-NULL, this global variable remains unchanged so.Each N _DWhen the dump incident takes place,, monitor this global variable according to the end of this dump.If HWQEmptyConter is more than or equal to threshold value (current is 2), then the paMultiplier field with pTLV increases I _MIn a word, HWQEmptyCounter can be reset to 0.

Increasing progressively of multiplier means increase upstream mandate speed.Ideally, for each N _D, scheduler should distribute enough mandates to transmit the frame of an extra serial at each RTT.Average size based on the MTD frame that is divided by with the paQuanta value is provided with increment I _MFor simplified design, I _MBe set to the serial connection threshold value of being divided by with the paQuanta value.This is not accurate fully, because the frame of some serial connections can be more much lower than the serial connection threshold value; (on the fly) calculates the on average needs of the size of the frame of serial connection yet this has eliminated in real time.

$I_M=\left[\frac{T_{\mathrm{CONCAT}}}{\mathrm{paQuanta}}\right]$ Equation 4

Apply restriction to increase efficient for paMultiplier.This restriction allows to keep deposit (backlog) when transmitting near CoS, feasiblely do not ask the mandate of Duoing than the mandate of needs.

When dump mirage packet, wish to obtain opposite result.Dump mirage packet means that formation is not used the whole mandates that just are being authorized to for empty and this modulator-demodulator.Desired bandwidth during by oblique deascension (rampdown) than slightly slow in oblique ascension (ramp up); Decrement value D thus _MTo be I _MProportional form.

D _M=[s * I _M] S ∈ (0,1] equation 5

P for each insertion ², paMultiplier should reduce D _MPaMultiplier can be less than zero.

The generation of pTLV and renewal

PTLV is configured and joins the EHDR of first frame of the frame of serial connection, if perhaps more simply, pTLV is configured and joins each frame.According to application, PTL will slowly change (BULK is faster than WEB) along with the time.When application was WEB, the paQuanta value will be along with the renewal of (widowing) algorithm of windowing (if use window) is changed at every turn.When application is BULK, the paQuanta value will remain unchanged, yet multiplier will or be worked as N when inserting the mirage packet at every turn _D ^TbFrame changes when being dumped to non-NULL HWQ.

The generation of Web pTLV and renewal

When request WEB preassignment, SM is transformed to use the quiescent value of paQuanta quantum unit (quanta unit), in 1250 to 3864 bytes range.

Transmit generation and the renewal of pTLV in batch

PTLV can make paQuanta _BULKBe set to fixed size.For initial integrated purpose, this size is 276 bytes (being converted to the quantum unit).When setting paQuanta big or small for BULK, there is balance between (only in the situation of paQuanta, paQuanta mandate afterwards is used to ineffectually carry fragment at frame) will making authorize to become big (to carry big frame potentially effectively) and make and authorize and diminish.The inventor thinks that littler mandate is better.

In order on small documents, to obtain more near the speed of CoS, be used for the preallocated paMultplier of BULK will from this restriction beginning also oblique deascension (if necessary) to correct speed.This feature is known as " skipping to CoS " (" Jump to Cos ").Under normal circumstances, when having non-contention speed limit factor (for example, the ftp server restriction), only can waste bandwidth.

Fair sharing and class of service

Minimum reserved rate

The original type scheduler algorithms of doing one's best in the STMS software provides and has utilized the minimum reserved rate of DOCSIS parameter.Be its qualification below.

This parameter is specified the minimum-rate that is preserved for this Business Stream, bps being unit.CMTS should satisfy its minimum bandwidth allocation request that keeps traffic rate that reaches that is used for Business Stream.If for traffic request than its minimum low bandwidth of traffic rate that keeps, CMTS can redistribute superfluous reserved bandwidth and be used for other purpose.The minimum traffic rate that keeps of the accumulation of all Business Streams may surpass amount of bandwidth available.After MAC HCS, calculate this value of this parameter to the byte of the CRC5 that ends up.If omit this parameter, then making its default value is 0 bps (be default be not to be this stream reserved bandwidth).

The type algorithm of doing one's best utilizes the normalized version (is unit with kilobytes) of this parameter to calculate each credit (credit) of accumulating by the mandate of DRR algorithm.Therefore, according to the class of service of stream, thereby this parameter can change this stream is provided weight with respect to other stream on the channel.

It should be noted that system discussed above, method and software are in fact only as example.Must emphasize that different embodiment can omit rightly, substitute or increase different processing or element.For example, be to be appreciated that in optional embodiment, can add, omit or merge different steps to be different from above-mentioned order manner of execution.Equally, the feature of describing for certain embodiment also can with other different embodiment combinations.The different aspects and the assembly that can merge embodiment in a similar manner.In addition, should be emphasized that technology is in development, many thus assemblies only are used for example and should be interpreted as limiting the scope of the invention.

In specification, provided specific detail so that the complete understanding of embodiment to be provided.Yet, will be understood by those skilled in the art that embodiment can not need these specific detail and is implemented.For example, show known circuit, processing, algorithm, result and technology and do not have unnecessary details, to avoid indigestion embodiment.

In addition, be to be further noted that embodiment can be described to the processing by flow chart, structure chart or block diagram representation.Though program process when they can be described as operation, many operations can walk abreast or generation simultaneously.In addition, the order of operation can be rearranged.Processing stops when complete operation, has the extra step that does not comprise in the drawings but handle.

In addition, can represent one or more devices that are used to store data at this term " storage medium " or " storage device ", comprise that read-only memory (ROM), random access memory (RAM), magnetic ram, core memory, magnetic disk storage medium, optical storage media, flash memory device or other are used for the computer-readable medium of stored information.Term " computer-readable medium " is including, but not limited to portable or fixed-storage device, light storage device, wireless channel, SIM card, other smart cards, and various other media that can store, comprise or carry instruction or data.

In addition, can make up by hardware, software, firmware, middleware, microcode, hardware description language or its and realize embodiment.When realizing, carry out in the machine readable media that the program code of necessary task or code segment can be stored in storage medium for example with software, firmware, middleware or microcode.Processor can be carried out necessary task.

Described some embodiment, those of ordinary skill in the art is to be appreciated that and can uses various modifications, optional structure or equivalence to replace and do not depart from spirit of the present invention.For example, top assembly can only be the element of bigger system, and wherein other rules can be replaced original rule or be revised application of the present invention.In addition, can consider to need a plurality of steps before the said modules.Thus, top description should not be considered to limit the scope of the present invention that is defined by claim.

Claims (18)

1. the preallocated method that is used for the upstream channel resource in the system of transmitting data via satellite comprises:

The scheduler that provides gateway satellite modem terminating systems (SMTS) to locate is used for using in response to the request of user terminal;

Detect in transmitting in batch at described user terminal place, described transmit in batch to comprise by upstream channel transmit from the mass data of described user terminal and transmit from the web of described user terminal; Thus

Be identified for the preallocated request of packet bandwidth; Then

From described user terminal to gateway SMTS transmit status and the preassignment of requested packet bandwidth and

Distribute superfluous transmission capacity at described gateway SMTS place to user terminal with loading demand.

2. method according to claim 1, the step of wherein said transmission comprises the transmission value field.

3. method according to claim 1, the step of wherein said transmission comprise transmission types length value (TLV) field.

4. method according to claim 1, the step of wherein said detection comprises perception transfer rate and storage level, is used for detecting in batch transmitting.

5. method according to claim 1, the step of wherein said detection comprise the perception of the visit of the port that is associated with the web inquiry, are used for detecting at least web and transmit.

6. method according to claim 5, the step of wherein said detection comprise perception data bag size, transfer rate and storage level, are used for detecting in batch transmitting.

7. method according to claim 1, the step that wherein said preassignment is determined comprise the preassignment bandwidth of specifying the preliminary election that is used for the web transmission.

8. the step that method according to claim 1, wherein said preassignment are determined comprises the preassignment bandwidth that stand-by storage history is specified be used for transmitting in batch.

9. method according to claim 1, the step of wherein said distribution comprise the web pre-allocation request of abandoning described user terminal if channel congestion surpasses threshold value.

10. the preallocated system that is used for the upstream channel resource in the system of transmitting data via satellite comprises:

The scheduler that gateway satellite modem terminating systems (SMTS) is located is used for using in response to the request of user terminal;

The processor at described user terminal place:

Be used for detecting in batch one that transmits, described transmit in batch to comprise by upstream channel transmit from the mass data of described user terminal and transmit from the web of described user terminal; Thus

Be used to be identified for the preallocated request of packet bandwidth; Then

Be used for from described user terminal to gateway SMTS transmit status and the preassignment of requested packet bandwidth and

Be used for distributing superfluous transmission capacity to user terminal with loading demand at described gateway SMTS place.

11. system according to claim 10, wherein said reflector can be operated and be used to send value field.

12. system according to claim 10, wherein said reflector can be operated and be used for transmission types length value (TLV) field.

13. system according to claim 10, the operation of the detection of wherein said processor comprises perception transfer rate and storage level, is used for detecting in batch transmitting.

14. system according to claim 10, the operation of the detection of wherein said processor comprises the perception of the visit of the port that is associated with the web inquiry, is used for detecting at least web and transmits.

15. system according to claim 14, the operation of the detection of wherein said described processor comprises perception data bag size, transfer rate and storage level, is used for detecting in batch transmitting.

16. system according to claim 10, the operation that the preassignment of wherein said processor is determined comprises the preassignment bandwidth of specifying the preliminary election that is used for the web transmission.

17. system according to claim 10, the operation that the preassignment of wherein said processor is determined comprises the preassignment bandwidth that stand-by storage history is specified be used for transmitting in batch.

18. system according to claim 10, the operation of the distribution of wherein said processor comprises the web pre-allocation request of abandoning described user terminal if channel congestion surpasses threshold value.

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